The Demons noticed Arthur's actions, especially since he killed a Transcendent right after entering and many were confused as they'd never seen any 3 Star General that looked as young as Arthur did.
But the Demon Generals, all of which had been briefed about Arthur's presence were not surprised by his appearance, only the fact that he just one-shot a level 910.
The boy didn't just go after Transcendents, he also assisted with lower ranked angels and divine humans as well.
His Pseudo-Authority of Destruction was active, and with it, he used 'Selective Destruction' to make his attacks ignore everything 'demonic' and only target everything 'divine'.
In the battlefield that was a cacophony of roars, clashes, and energy blasts, Arthur was a whirlwind of power that swept through.
'Extinction Slash.'
